The present invention relates to keyword extraction and, more specifically, to an extraction of a keyword in a claim.
Recently, the need for patent analysis is growing. The patent analysis is carried out for the purpose of detecting technical trends, hidden needs, competitors strategies, important technologies, or related patents to the company-owned technologies.
A patent analysis is carried out using text mining techniques, such as Natural Language Processing (NLP) based approaches, semantic analysis based approaches, rules based approached, property-function based approaches, and neural networks based approaches.
Various approaches for the patent analysis are proposed by the following Patent Literatures [1] and [2] and Non-patent Literatures [A] to [I]. However, there is no technique for extracting a keyword from a patent document with a high accuracy.    [1] US 2015/0178272 A1    [2] CN 105426546 A    [A] Toru Takaki et. al., “Associative Document Retrieval by Query Subtopic Analysis and its Application to Invalidity Patent Search”, ACM New York, Proceeding CIKM '04 Proceedings of the thirteenth ACM international conference on Information and knowledge management, pp. 399-405, November 2004.    [B] Fu-ren Lin et. al., “The Study of Patent Prior Art Retrieval Using Claim Structure and Link Analysis”, PACIS 2010 Proceedings, July 2010.    [C] Assad Abbas, “A literature review on the state-of-the-art in patent analysis”, Word Patent Information, Volume 37, pp. 3-13, June 2014.    [D] Akihiko Shinmori et. al., “Rhetorical Structure Analysis of Japanese Patent Claims using Cue Phrases”, Proceedings of the third NTCIR Workshop, pp. 69-77, 2013.    [E] Svetlana Sheremetyeva, “Natural Language Analysis of Patent Claims”, Proceeding PATENT '03 Proceedings of the ACL-2003 workshop on Patent corpus processing, Volume 20, pp. 66-73, 2003.    [F] Yiqun Chen et. al., “Novel word features for keyword extraction”, Web-Age Information Management, Volume 9098 of the series Lecture Notes in Computer Science, pp. 148-160, Jun. 6, 2015.    [G] Manisha Verma et. al., “Applying key phrase extraction to aid invalidity search”, Proceeding ICAIL '11 Proceedings of the 13th International Conference on Artificial Intelligence and Law, pp. 249-255, 2011.    [H] Heeyong Noh et. al., “Keyword selection and processing strategy for applying text mining to patent analysis”, Expert Systems with Applications, ELSEVIER, Volume 42 (9), pp. 4348-4360, Jun. 1, 2015.    [I] Svetlana. Sheremetyeva et. al., “Generating patent claims from interactive input”, Proceedings of the 8th. International Workshop on Natural Language Generation (INLG '96), pp. 61-70, June 1996